#1 thud n. [thump, thumping, clump, clunk] a heavy dull sound (as made by impact of heavy objects). wn
#2 thud v. [thump] make a dull sound; "the knocker thudded against the front door". wn
#3 thud v. strike with a dull sound; "Bullets were thudding against the wall". wn
#4 thud v. [crump, scrunch] make a noise typical of an engine lacking lubricants. wn
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